OBJECTIVE: To detect and characterize viruses or viral genetic markers in tissues from normal, hyperplastic, and malignant prostates and to determine the etiologic significance of the viruses in the origin of human prostatic cancer. APPROACH: Morphological, biological, immunological, and biochemical techniques are applied to detect virus particles or markers with properties similar or related to tumor viruses of other animal species in the normal or malignant tissues of human prostate. In addition, model system studies are carried out to determine host/virus relationships in cells derived from human prostate tissue and deliberately infected with viruses selected for known or suspected oncogenicity. These include Mason-Pfizer virus, simian sarcoma-associated virus (SSAV-1), and herpes simplex types 1 and 2.